Leaded gas was a known poison the day it was invented (2016)
Leaded gas was a known poison the day it was invented (2016)
含铅汽油在发明之初就被认定为剧毒（2016）
A Standard Stations filling station in California, circa 1939. Wikimedia Commons For most of the mid-twentieth century, lead gasoline was considered normal. It wasn’t: lead is a poison, and burning it had dire consequences. But how did it get into gasoline in the first place? 1939年左右，加利福尼亚州的一家标准石油（Standard Stations）加油站。（图片来源：维基共享资源）在20世纪中叶的大部分时间里，含铅汽油被视为常态。但事实并非如此：铅是一种毒药，燃烧它会带来可怕的后果。那么，它最初是如何进入汽油的呢？
The answer goes back to this day in 1921, when General Motors engineer named Thomas Midgley Jr. told his boss Charles Kettering that he’d discovered a new additive which worked to reduce the “knocking” in car engines. That additive: tetraethyl lead, also called TEL or lead tetraethyl, a highly toxic compound that was discovered in 1854. His discovery continues to have impact that reaches far beyond car owners. 答案要追溯到1921年的今天，当时通用汽车的工程师托马斯·米基利（Thomas Midgley Jr.）告诉他的老板查尔斯·凯特林（Charles Kettering），他发现了一种新的添加剂，可以减少汽车发动机的“爆震”现象。这种添加剂就是四乙基铅（TEL），这是一种发现于1854年的剧毒化合物。他的这一发现所产生的影响，至今仍远远超出了汽车拥有者的范畴。
Kettering himself had designed the self-starter a decade before, wrote James Lincoln Kitman for The Nation in 2000, and the knocking was a problem he couldn’t wait to solve. It made cars less efficient and more intimidating to consumers because of the loud noise. But there were other effective anti-knock agents. Kitman writes that Midgley himself said he tried any substance he could find in the search for an antiknock, “from melted butter and camphor to ethyl acetate and aluminum chloride.” 詹姆斯·林肯·基特曼（James Lincoln Kitman）在2000年为《国家》杂志撰文称，凯特林本人在十年前就设计了汽车自动启动装置，而“爆震”是他迫切想要解决的问题。这种噪音不仅降低了汽车的效率，还因其巨大的声响让消费者感到畏惧。但当时其实还有其他有效的抗爆剂。基特曼写道，米基利本人曾说，为了寻找抗爆剂，他尝试了所能找到的任何物质，“从融化的黄油和樟脑，到乙酸乙酯和氯化铝，应有尽有。”
The most compelling option was actually ethanol. But from the perspective of GM, Kitman wrote, ethanol wasn’t an option. It couldn’t be patented and GM couldn’t control its production. And oil companies like Du Pont “hated it,” he wrote, perceiving it to be a threat to their control of the internal combustion engine. TEL filled the same technical function as ethanol, he wrote: it reduced knock by raising the fuel’s combustability, what would come to be known as “octane.” 事实上，最令人信服的选择是乙醇。但基特曼写道，从通用汽车的角度来看，乙醇并非选项。因为它无法申请专利，通用汽车也无法控制其生产。此外，杜邦（Du Pont）等石油公司“非常讨厌它”，认为它威胁到了他们对内燃机的控制。他写道，四乙基铅在技术功能上与乙醇相同：它通过提高燃料的燃烧性能（即后来所知的“辛烷值”）来减少爆震。
Unlike ethanol, though, it couldn’t be potentially used as a replacement for gasoline, as it had been in some early cars. The drawback: it was a known poison, described in 1922 by a Du Pont executive as “a colorless liquid of sweetish odor, very poisonous if absorbed through the skin, resulting in lead poisoning almost immediately.” That statement is important, Kitman wrote: later, major players would deny they knew TEL to be so poisonous. 然而，与乙醇不同的是，它无法像早期某些汽车那样作为汽油的替代品。其缺点在于：它是一种已知的毒药。1922年，一位杜邦公司高管将其描述为“一种带有甜味的无色液体，如果通过皮肤吸收会产生剧毒，几乎会立即导致铅中毒。”基特曼写道，这一声明非常重要：因为后来，各大相关企业都否认他们曾知晓四乙基铅具有如此剧毒。
So in February 1923, a filling station sold the first tank of leaded gasoline. Midgley wasn’t there: he was in bed with severe lead poisoning, writes History.com. The next year, there was serious backlash against leaded gasoline after five workers died from TEL exposure at the Standard Oil Refinery in New Jersey, writes Deborah Blum for Wired, but still, the gasoline went into general sale later that decade. 于是，在1923年2月，一家加油站售出了第一箱含铅汽油。据History.com报道，米基利当时并不在场：他正因严重的铅中毒卧床不起。黛博拉·布鲁姆（Deborah Blum）为《连线》杂志撰文称，次年，在新泽西州标准石油炼油厂发生五名工人因接触四乙基铅而死亡的事件后，社会对含铅汽油产生了强烈的抵制，但即便如此，这种汽油还是在那个年代后期进入了全面销售。
In 1926, she writes, a public health service report concluded there was “no reason to prohibit the sale of leaded gasoline” so long as workers were protected when they made it. Blum continues: The task force did look briefly at risks associated with every day exposure by drivers, automobile attendants, gas station operators, and found that it was minimal. The researchers had indeed found lead residues in dusty corners of garages. In addition, all the drivers tested showed trace amounts of lead in their blood. But a low level of lead could be tolerated, the scientists announced. 她写道，1926年，一份公共卫生服务报告得出结论称，只要工人在生产过程中受到保护，就“没有理由禁止销售含铅汽油”。布鲁姆继续写道：工作组确实简要调查了司机、汽车服务员和加油站操作员日常接触的风险，并认为风险极小。研究人员确实在车库的角落里发现了铅残留物。此外，所有接受测试的司机血液中都显示有微量的铅。但科学家们宣布，低水平的铅是可以耐受的。
That report acknowledged that exposure levels might rise over time. “But, of course, that would be another generation’s problem,” she writes. Those early actions set a precedent that was hard to undo: it wouldn’t be until the mid-1970s that a growing body of evidence about the dangers of leaded gasoline lead the EPA to enter into a years-long legal struggle with gasoline-makers over phasing out leaded gasoline. 该报告承认，接触水平可能会随时间推移而上升。“但当然，那将是下一代人的问题了，”她写道。这些早期的行为开创了一个难以扭转的先例：直到20世纪70年代中期，随着关于含铅汽油危害的证据越来越多，美国环保署（EPA）才开始与汽油制造商展开长达数年的法律斗争，以逐步淘汰含铅汽油。
The effects of so much lead being burned and forced into the air are still being felt in the United States and other countries where leaded gasoline was—or still is—used. “Chidren are the first and worst victims of leaded gas; because of their immaturity, they are most susceptible to systemic and neurological injury,” wrote Kitman. Research has shown that lead exposure in children is linked to “a whole raft of complications later in life,” writes Kevin Drum for Mother Jones, among them lower IQ, hyperactivity, behavioral problems and learning disabilities. 大量铅被燃烧并排入空气所带来的影响，至今仍在影响着美国以及其他曾经或仍在继续使用含铅汽油的国家。“儿童是含铅汽油的首要且最严重的受害者；由于发育尚不成熟，他们最容易受到全身性和神经系统的伤害，”基特曼写道。凯文·德拉姆（Kevin Drum）在为《琼斯母亲》杂志撰文时写道，研究表明，儿童时期的铅接触与“日后生活中的一系列并发症”有关，其中包括智商降低、多动症、行为问题和学习障碍。
A significant body of research links lead exposure in children to violent crime, he writes. Much of that lead is still around in environments that were contaminated by gasoline fumes during the era of unleaded. It’s a problem that can’t be left for another generation, Drum writes. 他写道，大量研究将儿童时期的铅接触与暴力犯罪联系起来。在无铅汽油时代之前，许多环境曾被汽油烟雾污染，而大部分铅至今仍残留在这些环境中。德拉姆写道，这是一个不能留给下一代去解决的问题。